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This is the Nearest One Head
P U Z Z L E R
More than 300 years ago, Isaac Newton
realized that the same gravitational force
that causes apples to fall to the Earth
also holds the Moon in its orbit. In recent
years, scientists have used the Hubble

P U Z Z L E R
One of the most popular early bicycles
was the penny farthing, introduced in
1870. The bicycle was so named because
the size relationship of its two wheels
was about the same as the size relationship of the penny and the farthing, two
Englis

P U Z Z L E R
The Spirit of Akron is an airship that is
more than 60 m long. When it is parked
at an airport, one person can easily support it overhead using a single hand.
Nonetheless, it is impossible for even a
very strong adult to move the ship
abrupt

P U Z Z L E R
This airplane is used by NASA for astronaut training. When it ies along a certain curved path, anything inside the
plane that is not strapped down begins to
oat. What causes this strange effect?
(NASA)
web
For more information on microgravit

P U Z Z L E R
In a moment the arresting cable will be
pulled taut, and the 140-mi/h landing of
this F/A-18 Hornet on the aircraft carrier
USS Nimitz will be brought to a sudden
conclusion. The pilot cuts power to the
engine, and the plane is stopped in le